Abstract: A method and device is provided for simply and rapidly measuring erythrocyte deformability by placing samples of blood on a set of porous membranes or a membrane strip with graded series of sharply defined pore sizes to determine the selective absorption thereon. Based on observation of the selective absorption on the membranes or membrane strip the deformability index of the erythrocytes may be determined.

Abstract: Microfiltration membranes are described comprising 10% to 50% cyanoethylated polysaccharide ether polymers blended with 50% to 90% polymers of cellulose nitrate, cellulose acetate or mixtures of the two. These membranes are flexible and strong and can be readily pleated for use in cartridge filters as well as used flat in conventional single- or multi-plate holders. They are also more thermally stable than conventional "mixed ester" (cellulose nitrate/cellulose acetate) membranes.

Abstract: A method for forming a microporous sheet of fluorocarbon polymer (e.g., polytetrafluoroethylene). An aqueous dispersion of polytetrafluoroethylene which includes a dissolved water-soluble, crystallizable metallic organic salt, preferably sodium benzoate, is formed into a sheet. Water is evaporated from an exposed surface of the sheet to grow crystals of the organic salt dispersed throughout the sheet. Then, the sheet is sintered. After cooling, the salt crystals are leached from the sheet by dissolution in water to leave a porous structure suitable for such uses as a filtration membrane or as a separation barrier in batteries or electrolytic cells.

Abstract: A microporous filter having pleated filter cartridge is provided with inlet and bypass ports for establishing tangential flow across outside boundary of cartridge inlet side resulting in slow clogging operation.